Luiz said those defeats were consigned to history, but added: "The first few days were very difficult.

"When you don't achieve an objective you're disappointed, but football gives you a chance to bounce back quickly. It gives you the opportunity to learn quickly, to see where you made mistakes, to improve.

"I now have a great opportunity, and I'm ready to help this club shine in the world."

After the defender's departure from Stamford Bridge, Mourinho claimed he would not miss him.

"I think it's normal," Luiz said. "If he said he was missing me, he would contradict himself.

"What matters now is the advice of Laurent Blanc. Chelsea is in the past. I look forward to the present, which is bright, because I have the chance to play for a big club with a marvellous project for the future."

Luiz will replace Alex, who left on a free transfer for AC Milan earlier this summer, at the heart of PSG's defence alongside compatriot Thiago Silva. The pair also form the first-choice centre-back pairing for their country.

"We're good friends, and we've played together a long time. We understand each other easily on the pitch," he said. "We're very alert on the pitch, united. We always give the best of ourselves and adapt."